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Pikeperch (Sander lucioperca) is a highly valuable fish in Europe. However, development of aquaculture of pikeperch is highly limited due to seasonality of production. This can be overcome by the controlled reproduction of domesticated fish. The first steps of domestication process may induce changes at anatomical, physiological and molecular levels, thereby affecting a variety of biological functions. While there is abundant literature on their effects on stress and growth for example, these effects on reproduction received limited attention notably in pikeperch, a promising candidate for the development of aquaculture. To answer the question of this life-history effect on pikeperch’s reproduction, we compared two groups (weight: 1 kg) originated from Czech Republic and with the same domestication level (F0). The first group was a recirculating aquatic system cultured one (2 years, previously fed with artificial diet, never exposed to natural changes in temperature/photoperiod conditions) and the second one was a pond cultured group (3 to 4 years, bred under natural feeding and temperature/photoperiod). The wild group successfully spawned, while the farmed one did not spawn at all. During the program, gonadosomatic indexes of both males and females were significantly higher for the wild fish, as well as the sexual steroids. Gene expression analysis revealed significantly lower LH transcript levels at the pituitary level for the farmed females and lower FSH transcript levels at the pituitary level for the males. In conclusion this study showed that the previous rearing conditions (e.g. culture system, age, diet, etc.) alter the further progress of gametogenesis and the reproductive performances in response to controlled photothermal program for both sexes in pikeperch.
Populations of the White-rumped Vulture Gyps bengalensis, Indian Vulture G. indicus and Slender-billed Vulture G. tenuirostris declined rapidly during the mid-1990s all over their ranges in the Indian subcontinent because of poisoning due to veterinary use of the non-steroidal anti-inflammatory drug diclofenac. This paper reports results from the latest in a series of road transect surveys conducted across northern, central, western and north-eastern India since the early 1990s. Results from the seven comparable surveys now available were analysed to estimate recent population trends. Populations of all three species of vulture remained at a low level. The previously rapid decline of White-rumped Vulture has slowed and may have reversed since the ban on veterinary use of diclofenac in India in 2006. A few thousand of this species, possibly up to the low tens of thousands, remained in India in 2015. The population of Indian Vulture continued to decline, though probably at a much slower rate than in the 1990s. This remains the most numerous of the three species in India with about 12,000 individuals in 2015 and a confidence interval ranging from a few thousands to a few tens of thousands. The trend in the rarest species, Slender-billed Vulture, which probably numbers not much more than 1,000 individuals in India, cannot be determined reliably.
Persistence of the embryonic “fifth aortic arch” in postnatal life is a rare, enigmatic – and at times controversial – condition, with variable anatomical forms and physiological consequences. First described in humans over 40 years ago by Van Praagh, the condition was labelled the “great pretender” by Gerlis 25 years later, because of its apparent propensity to mimic anatomically similar structures. Despite many subsequent case reports citing the condition, the true developmental origin of these structures remains unresolved, and has been the subject of debate among embryologists for more than a century. A persistent fifth aortic arch has been defined as an extrapericardial structure, arising from the ascending aorta opposite or proximal to the brachiocephalic artery, and terminating in the dorsal aorta or pulmonary arteries via a persistently patent arterial duct. This description may therefore encompass various anatomical forms, such as a unilateral double-lumen aortic arch, an unrestrictive aortopulmonary shunt, or a critical vascular channel for either the systemic or pulmonary circulation. The physiological properties of these vessels, such as their response to prostaglandins, may also be unpredictable. In this article, we demonstrate a number of cases that fulfil the contemporary definition of “persistent fifth aortic arch” while acknowledging the embryological controversies associated with this term. We also outline the key diagnostic features, particularly with respect to the use of new cross-sectional imaging techniques.
Vortex-induced vibration (VIV) is an important physical phenomenon as one design a riser or a cylindrical structure in ocean. As the riser or the cylindrical structure is adjacent to a seabed, the boundary effect on VIV is not fully understood yet. The direct-forcing immersed boundary (DFIB) method is used to investigate a two-degree-of-freedom VIV of a flexible supported circular cylinder adjacent to a plane boundary in this study. Furthermore, the effect of the VIV of cylinder on skin friction of the plane boundary is investigated. The effects of varying reduced velocity and gap ratio on VIV are discussed. Only a single vortex street is found when the cylinder is close to plane boundary. Hydrodynamic coefficients of the freely vibrating cylinder are analyzed in time and spectral domains. Furthermore, nearly round oval-shaped motion is observed as the so-called lock-in phenomenon occurs. The skin friction of the plane boundary is predicted by the DFIB model. Results show that the vibrating cylinder in the boundary layer flow can reduce the friction effectively. This proposed DFIB model can be useful for the investigation of VIV of the structures under the plane boundary effect even for a small gap between the cylinder and the boundary.
Total birth records for the Bengalee Muslim population (BMP) and the Bengalee Hindu caste population (BHCP) for the period 1980-1988 were 17,720 and 119,107 respectively. Of these, the number of twin pairs were 363 BMP and 1,229 BHCP. These data were obtained from the registers of the following hospitals: Islamia Hospital, NRS Medical College and Hospitals and RG Kar Medical College and Hospitals, Calcutta and Medinipore Sadar Hospital, West Bengal, India. The twinning rates found were 20.48 and 10.57 per thousand deliveries in the BMP and BHCP respectively. The proportion of twins, 0.02048, in the BMP was significantly higher (Z = 12.38, p ≤ 0.01) than that in the BHCP, 0.01057. This finding of a higher twinning rate in the BMP is corroborated by the fact that available data on the Muslim population of Srinagar in Kammu and Kashmir, and Lucknow and Kanpur in Uttar Pradesh show higher twinning rates than the other populations of India. This increased twinning rate may be due to the greater amount of inbreeding in the BMP.
Quasi-one-dimensional (quasi-1D) tools developed for capturing flow and acoustic dynamics in non-segmented solid rocket motors are evaluated using multi-dimensional computational fluid dynamic simulations and used to characterise damping of modal perturbations. For motors with high length-to-diameter ratios (of the order of 10), remarkably accurate estimates of frequencies and damping rates of lower modes can be obtained using the the quasi-1D approximation. Various grain configurations are considered to study the effect of internal geometry on damping rates. Analysis shows that lower cross-sectional area at the nozzle entry plane is found to increase damping rates of all the modes. The flow-turning loss for a mode increases if the more mass addition due to combustion is added at pressure nodes. For the fundamental mode, this loss is, therefore, maximum if burning area is maximum at the centre. The insights from this study in addition to recommendations made by Blomshield(1) based on combustion considerations would be very helpful in realizing rocket motors free from combustion instability.
Synonymous codons are used with different frequencies, a phenomenon known as codon bias, which exists in many genomes and is mainly resolute by mutation and selection. To elucidate the genetic characteristics and evolutionary relationship of Wucheraria bancrofti and Schistosoma haematobium we examined the pattern of synonymous codon usage in nuclear genes of both the species. The mean overall GC contents of W. bancrofti and S. haematobium were 43.41 and 36.37%, respectively, which suggests that genes in both the species were AT rich. The value of the High Effective Number of Codons in both species suggests that codon usage bias was weak. Both species had a wide range of P3 distribution in the neutrality plot, with a significant correlation between P12 and P3. The codons were closer to the axes in correspondence analysis, suggesting that mutation pressure influenced the codon usage pattern in these species. We have identified the more frequently used codons in these species, most codons ending with an A or T. The nucleotides A/T and C/G were not proportionally used at the third position of codons, which reveals that natural selection might influence the codon usage patterns. The regression equation of P12 on P3 suggests that natural selection might have played a major role, while mutational pressure played a minor role in codon usage pattern in both species. These results form the basis of exploring the evolutionary mechanisms and the heterologous expression of medically important proteins of W. bancrofti and S. haematobium.
An investigation was carried out to study the growth, mortality and exploitation of bigeye scad, Selar crumenophthalmus off the Mumbai coast during September 2008 to August 2009. The von Bertalanffy growth equation was derived as Lt = 310 mm [1−exp {−1.4 year−1 × (t−(−0.059 year))}] with the growth performance index (ø’) of 3.13. The fishable lifespan of the species was 2+ years in Mumbai waters. Bigeye scad attains total length of 240 and 293 mm during its first and second year of life. The size at first capture (Lc) was estimated as 240 mm (1+ year). The recruitment was continuous and throughout the year with a single pulse during August. Nearly 50% of the recruitment took place during August and September. The total, natural and fishing mortality rates were 4.62, 2.21 and 2.41 year−1, respectively. The estimated exploitation ratio (0.52) was very close to the optimum value of 0.5. Hence, the stock can be considered as optimally over-exploited in Mumbai waters.
Drinking raw date palm sap is the primary route of Nipah virus (NiV) transmission from bats to people in Bangladesh; subsequent person-to-person transmission is common. During December 2010 to March 2011, we investigated NiV epidemiology by interviewing cases using structured questionnaires, in-depth interviews, and group discussions to collect clinical and exposure histories. We conducted a case-control study to identify risk factors for transmission. We identified 43 cases; 23 were laboratory-confirmed and 20 probable. Thirty-eight (88%) cases died. Drinking raw date palm sap and contact with an infected person were major risk factors; one healthcare worker was infected and for another case transmission apparently occurred through contact with a corpse. In absence of these risk factors, apparent routes of transmission included drinking fermented date palm sap. For the first time, a case was detected in eastern Bangladesh. Identification of new epidemiological characteristics emphasizes the importance of continued NiV surveillance and case investigation.
Background: A definitive diagnosis of multiple sclerosis (MS), as distinct from a clinically isolated syndrome, requires one of two conditions: a second clinical attack or particular magnetic resonance imaging (MRI) findings as defined by the McDonald criteria. MRI is also important after a diagnosis is made as a means of monitoring subclinical disease activity. While a standardized protocol for diagnostic and follow-up MRI has been developed by the Consortium of Multiple Sclerosis Centres, acceptance and implementation in Canada have been suboptimal. Methods: To improve diagnosis, monitoring, and management of a clinically isolated syndrome and MS, a Canadian expert panel created consensus recommendations about the appropriate application of the 2010 McDonald criteria in routine practice, strategies to improve adherence to the standardized Consortium of Multiple Sclerosis Centres MRI protocol, and methods for ensuring effective communication among health care practitioners, in particular referring physicians, neurologists, and radiologists. Results: This article presents eight consensus statements developed by the expert panel, along with the rationale underlying the recommendations and commentaries on how to prioritize resource use within the Canadian healthcare system. Conclusions: The expert panel calls on neurologists and radiologists in Canada to incorporate the McDonald criteria, the Consortium of Multiple Sclerosis Centres MRI protocol, and other guidance given in this consensus presentation into their practices. By improving communication and general awareness of best practices for MRI use in MS diagnosis and monitoring, we can improve patient care across Canada by providing timely diagnosis, informed management decisions, and better continuity of care.
The West Virginia University Hot hELIcon eXperiment (HELIX) provides variable density and ion temperature plasmas, with controllable levels of thermal anisotropy, for space relevant laboratory experiments in the Large Experiment on Instabilities and Anisotropy (LEIA) as well as fundamental studies of helicon source physics in HELIX. Through auxiliary ion heating, the ion temperature anisotropy (T⊥/T∥) is variable from 1 to 20 for parallel plasma beta (β = 8πnkTi∥/B2) values that span the range of 0.0001 to 0.01 in LEIA. The ion velocity distribution function is measured throughout the discharge volume in steady-state and pulsed plasmas with laser induced fluorescence (LIF). The wavelengths of very short wavelength electrostatic fluctuations are measured with a coherent microwave scattering system. Operating at low neutral pressures triggers spontaneous formation of a current-free electric double layer. Ion acceleration through the double layer is detected through LIF. LIF-based velocity space tomography of the accelerated beam provides a two-dimensional mapping of the bulk and beam ion distribution functions. The driving frequency for the m = 1 helical antenna is continuously variable from 8.5 to 16 MHz and frequency dependent variations of the RF coupling to the plasma allow the spontaneously appearing double layers to be turned on and off without modifying the plasma collisionality or magnetic field geometry. Single and multi-species plasmas are created with argon, helium, nitrogen, krypton, and xenon. The noble gas plasmas have steep neutral density gradients, with ionization levels reaching 100% in the core of the plasma source. The large plasma density in the source enables the study of Aflvén waves in the HELIX device.
Head and face dimensions vary according to race and geographical zone. Hereditary factors also greatly affect the size and shape of the head. There are important medical applications of craniofacial data specific to different racial and ethnic groups.
Methods:
Various cranial and facial anthropometric parameters were assessed in singleton, healthy, full-term newborns of Sikkimese origin in a tertiary care hospital in Sikkim, India. The data were then analysed to determine statistically significant differences between sexes.
Results:
Forty-five newborns were included in the study. Both male and female newborns were observed to be hyperbrachycephalic and hyperleptoprosopic. The only significant difference between the sexes was in commissural length, which was observed to be greater in male newborns.
Conclusion:
Craniofacial parameters in Sikkimese newborns vary in comparison with those of other newborns from around the world. Larger studies are needed in order to reveal sex-related variations. Similar studies on various racial groups in North-East India are needed to establish standards for populations with East Asian features.
Socio-behavioural factors and pathogens associated with childhood diarrhoea are of global public health concern. Our survey in 696 children aged ⩽2 years in rural West Bengal detected rotavirus as sole pathogen in 8% (17/199) of diarrhoeic stool specimens. Other organisms were detected along with rotavirus in 11% of faecal specimens. A third of the children with rotavirus diarrhoea, according to Vesikari score, had severe illness. The top four rotavirus genotypes were G9P[4] (28%), G1P[8] (19%), G2P[4] (14%) and G8P[4] (8%). In the multivariate model, the practice of ‘drawing drinking water by dipping a pot in the storage vessel’ [adjusted odds ratio (aOR) 2·21, 95% confidence interval (CI) 1·03–4·74, P = 0·041], and ‘children aged ⩽6 months with non-exclusive breastfeeding’ (aOR 2·07, 95% CI 1·1–3·82, P = 0·024) had twice the odds of having diarrhoea. Incidence of rotavirus diarrhoea was 24/100 child-years in children aged >6–18 months, 19/100 child-years in children aged >18–24 months and 5/100 child-years in those aged ⩽6 months. Results have translational implications for future interventions including vaccine development.
Direct numerical simulation (DNS) of liquid film flow is used to compute fully developed solitary waves and to compare their characteristics with the predictions of low-dimensional models. Emphasis is placed on the regime of high inertia, where available models provide widely differing results. It is found that the parametric dependence of wave properties on inertia is highly non-trivial, and is satisfactorily approximated only by the four-equation model of Ruyer-Quil & Manneville (Eur. Phys. J. B, vol. 15, 2000, pp. 357–369). Detailed comparison of the asymptotic shapes of upstream and downstream tails is performed, and inherent limitations of all long-wave models are revealed. Local flow reversal in front of the main hump, which has been previously discussed in the literature, is shown to occur for an inertia range bounded from below and from above, and the boundaries are interpreted in terms of the capillary origin of the phenomenon. Computational results are reported for the entire range of Froude numbers, providing benchmark data for all wall inclinations.
Bimodal Atomic Force Microscopy (AFM) is a recently developed dynamic AFM technique. Recent work [1] has shown the existence of different regimes of operation in Bimodal AFM depending on the operating conditions. The current work focuses on the effects of different operating parameters while imaging an impact copolymer blend of polypropylene (PP) and ethylene-propylene (E-P) rubber. The higher mode amplitude and phase contrasts reverse at different points between the PP and rubber regions as the free amplitude of the higher eigenmode is increased. The observed contrast reversal suggests that the cantilever kinetic energy and its free air drive input energy play a role in determining the regimes of operation. Understanding the role of cantilever dynamics in determining these operation regimes will help guide a more rational operation of Bimodal AFM.
Diarrhoeal management practices are unsatisfactory in India especially in the slum areas. Dearth of information regarding physicians' diarrhoea-related knowledge and practice in India ncessitated this cross-sectional study of allopathic practitioners in the slums of Kolkata, to assess the distribution and interrelationship between physicians' characteristics, knowledge and practice regarding diarrhoea. A total of 264 randomly selected consenting practitioners were interviewed using a field-tested questionnaire. Nineteen percent had good overall knowledge, 49% and 80% prescribed antibiotics to diarrhoea and cholera patients, respectively, and 55% advised stool examination for every case. Qualified and Government physicians had better knowledge regarding diarrhoea [MBBS: odds ratio (OR) 5·96, P < 0·001; postgraduates: OR 9·33, P < 0·001; Government physicians: OR 11·49, P < 0·0001] and were less likely to prescribe antibiotics for all diarrhoea cases (MBBS: OR 0·30, P = 0·002; postgraduates: OR 0·20, P < 0·001; Government physicians OR 0·24, P < 0·029). Better knowledge was associated with a lower likelihood of prescribing antibiotics for diarrhoea (OR 0·72, P < 0·001), cholera (OR 0·78, P = 0·027) and investigative procedure (OR 0·85, P = 0·028). In the slums of Kolkata, diarrhoea-related knowledge and practice were poor with the exception of qualified physicians, hence an improvement in the knowledge of pharmacists and unqualified practitioners is necessary for the overall improvement of diarrhoeal management in these slums.
We consider a power-law fluid flowing down an inclined plane under the action of gravity. The divergence of the viscosity at zero strain rate is taken care of by introducing a Newtonian plateau at small strain rate. Two-equation models are formulated within the framework of lubrication theory in terms of the exact mass balance and an averaged momentum equation, which form a set of evolution equations for the film thickness , a local velocity amplitude or the flow rate . The models account for the streamwise diffusion of momentum. Comparisons with Orr–Sommerfeld stability analysis and with direct numerical simulation (DNS) show convincing agreement in both linear and nonlinear regimes. The influence of shear-thinning or shear-thickening on the primary instability is shown to be non-trivial. A destabilization of the base flow close to threshold is promoted by the shear-thinning effect, whereas, further from threshold, it tends to stabilize the base flow when the viscous damping of short waves becomes dominant. A reverse situation is observed in the case of shear-thickening fluids. Shear-thinning accelerates solitary waves and promotes a subcritical onset of travelling waves at larger wavenumber than the linear cut-off wavenumber. A conditional stability of the base flow is thus observed. This phenomenon results from a reduction of the effective viscosity at the free surface. When compared with DNS, simulations of the temporal response of the film based on weighted residual models satisfactorily capture the conditional stability of the film.